Active energy ray curable composition for coating optical disk and optical disk

1. An active energy ray curable composition for coating optical disc, comprising a urethane (meth)acrylate compound (A) having at least one amide group in the molecule, an ethylenically unsaturated compound (B) other than the urethane (meth)acrylate compound (A) and a photopolymerization initiator (C) wherein the urethane (meth)acrylate compound (A) is a urethane (meth)acrylate compound obtained by reacting the following components (a1) to (a4):

(a1) an amide-containing compound having two hydroxy groups and at least one amide group in the molecule,

(a2) a poly-hydric alcohol compound other than said component (a1),

(a3) a diisocyanate compound, and

(a4) a hydroxy group-containing (meth)acrylate and wherein

the component (a1) is an amide-containing compound obtained by reacting a cyclic hydroxy carboxylate and an amine compound, and

the ethylenically unsaturated compound (B) contains a mixture of

a compound of the following general formula (I) wherein X 3 is a hydroxy group, and

a compound of the following general formula (I) wherein X 3 is an acryloyloxy group or methacryloyloxy group:

wherein, and X 1 and X 2 represent an acryloyloxy group or methacryloyloxy group, X 3 represents a hydroxy group, acryloyloxy group or methacryloyloxy group, and R 1 , R 2 and R 3 represent an alkyl group having 1 to 4 carbon atoms.

2. The active energy ray curable composition for coating optical disc as claimed in claim 1 wherein the cyclic hydroxy carboxylate is at least one selected from the group consisting of γ-butyrolactone, δ-valerolactone and ε-caprolactone.

3. The active energy ray curable composition for coating optical disc as claimed in claim 1 wherein the amine compound is at least one selected from the group consisting of ethanolamine, diethanolamine, N-methylethanolamine, N-ethylethanolamine, N-phenylethanolamine, 2-amino-1-butanol, 2-amino-2-ethyl-1, 3-propanediol, 6-amino-1-hexanol, 1,4-diaminobutane, 1,2-diaminocyclohexane and 1,10-diamino-decane.

4. The active energy ray curable composition for coating optical disc as claimed in claim 1 wherein component (a1) is N-methyl-N-(2-hydroxyethyl)-3-hydroxypropylamide.

5. The active energy ray curable composition for coating optical disc according to claim 1 wherein the component (a2) is at least one diol compound selected from the group consisting of polyether diols, polyester diols and polycarbonate diols.

6. The active energy ray curable composition for coating optical disc according to claim 1 wherein the component (a3) is an alicyclic diisocyanate.

7. The active energy ray curable composition for coating optical disc according to claim 1 wherein the ethylenically unsaturated compound (B) contains a bisphenol type epoxy (meth)acrylate compound (b1).

8. A method comprising coating an optical disc with the active energy ray curable composition for coating optical disc as claimed in claim 1 .